Electronic devices such as a washing machine use a jog dial to allow a user to select a desired course from various work courses that the electronic device can perform.
An example of a conventional jog dial used in the electronic devices is illustrated in FIG. 1.
Referring to FIG. 1, the conventional jog dial 1 includes a dial knob 3 and a potential meter 5. The potential meter 5 is provided on a circuit board 6 for controlling an electronic device, and the circuit board 6 is disposed below an operation panel 9 provided in a case of the electronic device. Therefore, the potential meter 5 is located below the operation panel 9. Also, a rotating shaft 7 coupled with the dial knob 3 is provided at the center of the potential meter 5. The rotating shaft 7 of the potential meter 5 passes through the operation panel 9 of the electronic device and protrudes upward. The dial knob 3 is coupled to the rotating shaft 7 of the potential meter 5 above the operation panel 9 of the electronic device. Accordingly, when the user turns the dial knob 3, the rotating shaft 7 coupled to the dial knob 3 is rotated. When the rotating shaft 7 rotates, a value output from the potential meter 5 changes. A controller of the circuit board 6 may recognize a position of the dial knob 3 by receiving the value output from the potential meter 5. Accordingly, if the values output from the potential meter 5 are matched with various work courses that can be perforated by the electronic device, the user may select a desired work course by rotating the dial knob 3.
However, since the conventional jog dial 1 is provided with the dial knob 3 and the potential meter 5 which are mechanically coupled to each other, when the jog dial 1 is aged, the dial knob 3 may not rotate smoothly, or the connection portion between the dial knob 3 and the rotating shaft 7 may be broken.
In addition, when the potential meter 5 is aged, there is a problem that the potential meter 5 may be damaged or a recognition error may occur.
Also, since the operation panel 9 of the electronic device is provided with a through hole 8 through which the rotating shaft 7 of the potential meter 5 passes, there is a problem that the circuit board 6 may be damaged by moisture that enters into the inside of the operation panel 9 through the through hole 8.
In addition, since the conventional jog dial 1 has a structure in which the dial knob 3 and the rotating shaft 7 of the potential meter 5 are mechanically coupled to each other, there is a design limitation that the dial knob 3 must have a certain height or more for the coupling of the dial knob 3 and the rotating shaft 7. Accordingly, there is a problem that the conventional jog dial 1 itself becomes a restriction factor in the design of the electronic device.